Absorber including by-pass channel member and absorber product therefrom

ABSTRACT

An absorber comprising a laminate of two or more layers of highly water-absorbent sheets each containing a highly water-absorbent resin in high proportion, which absorber can satisfactorily cope with the feeding speed of aqueous liquid. In particular, an absorber comprising a laminate water-absorbent member, the laminate water-absorbent member consisting of a laminate of two or more layers of highly water-absorbent sheets each containing a highly water-absorbent resin and capable of absorbing an aqueous liquid, and a by-pass channel member, the by-pass channel member having a channel for, providing that an upper side refers to the side of laminate water-absorbent member fed with the aqueous liquid, moving the aqueous liquid fed to a first highly water-absorbent sheet disposed at the uppermost part of the laminate water-absorbent member from the first highly water-absorbent sheet to another highly water-absorbent sheet.

TECHNICAL FIELD

The present invention relates to an absorber which is applied to variousabsorbent products as an element constituting the main part of itsabsorptive function, more precisely, to an absorber which can quicklyabsorb aqueous liquid when a large amount of it is fed in a short periodof time to the surface of the absorber as a result of excretion.

Furthermore, the present invention relates to absorbent products such aspaper diapers, sanitary napkins, and incontinence products, using theabsorber.

BACKGROUND ART

An absorbent product includes an absorber as its primary component. Atpresent, in most of absorbent products available in the market, theabsorber is structured as a single layer of a mixture made ofsuper-absorbent polymer (also referred to as “SAP” hereinafter) andpulp. This single layer structure is sometimes formed with itscomponents uniformly distributed in a single layer, but in general, itjust has the appearance of being a single layer.

In other words, these absorbers, whose main component is pulp, arestructured, in general, to have a gradient in a concentrationdistribution of the SAP and the pulp. Specifically, the single layerstructure is formed of, most commonly, an upper layer primarilyconsisting of pulp, a middle layer primarily of SAP, and a bottom layerprimarily of pulp, by compressing and bonding these three layers ofdifferent constitution from one another into one, and further by theso-called “core wrapping” process in which the above is wrapped withtissue and non-woven fabric, to prevent desorption and scattering ofpulp and SAP.

Incidentally, in recent years, research and development insuper-absorbent sheet containing fibrous and powder SAP in highproportion as a single-layer-structure absorber has been activelycarried out.

For applications that do not require a great absorbing capacity, such assanitary napkins, slight-incontinence products for women, etc., thissuper-absorbent sheet is most commonly used as a single layer ratherthan stacking the sheets to form multiple layers, but for applicationsthat require a great absorbing capacity, such as baby diapers, adultincontinence diapers, etc., the super-absorbent sheets are generallylaminated to make a double-layer or triple-layer to give the requiredabsorbing capacity. Because this super-absorbent sheet is much thinnerthan the afore-mentioned conventional absorber whose main component ispulp, the super-absorbent sheet can be used in a laminate of multiplelayers as described above. Moreover, it has an advantage of being farthinner, even when it is used as a laminated structure of multiplelayers, than the conventional absorber whose main component is pulp.

In cases where the super-absorbent sheets are laminated to form multiplelayers as mentioned above, if the afore-mentioned super-absorbent sheetsare simply stacked to form the multiple-layer-structure, due to spacesbetween respective layers, aqueous liquid such as excreted urine thatseeps into the first, or top, layer cannot be uniformly transferred tothe second or further lower layers. As a result, it will be difficult tofully function as an absorber. These super-absorbent sheets, therefore,are used, in case these super-absorbent sheets are laminated to formmultiple layers, by making them into one body using adhesive or otherbonding material. Thus the extremely thin absorber with a greatabsorbing capacity potential can be obtained by laminating thesuper-absorbent sheets in multiple layers.

In real-life situations, however, the absorber which can be obtained bylaminating the super-absorbent sheets in multiple layers has adisadvantage that its absorbing speed cannot keep up with the speed ofthe excreted liquid that flows into the absorber, which results in itsleaking easily, without exerting its inherent absorbing capability.

According to the research by the inventors of the present invention, alimit of the speed of absorption by swelling of the SAP due tocharacteristics of the SAP and the aqueous liquid, and insufficientspace for liquid retention due to the absorber's extreme thinness arecited as causes for the disadvantage described above. In addition tothese, it has also been identified that the overall rate of utilizationof the absorbent is lowered by SAP's tendency to cause blocking, on topof its slow absorbing speed, though its absorbing capacity is extremelyhigh in comparison to the pulp, the main component of the conventionalabsorber, whose absorbing capacity is small though its absorbing speedis high.

Because in case two or more super-absorbent sheets are laminated, theabove problem becomes even more evident, research for a method of makingthe aqueous liquid fed to the top super-absorbent sheet seep into othersuper-absorbent sheets quickly and uniformly have been conducted and atechnique of inserting between respective layers highly hydrophilicnon-woven fabrics as diffusion sheets, a technique of physically makinglarge apertures or cutting slits and the like have been proposed, but sofar no effective solution has been found. With this background, while anadvent of absorbent products comprising the laminated super-absorbentsheets in multiple layers has been desired, it has not yet been realizedso far.

DISCLOSURE OF THE INVENTION

An object of the present invention, therefore, is to provide an absorberwhich can satisfactorily cope with the feeding speed of aqueous liquidinto the absorber, comprising two or more laminated super-absorbentsheets, each of which containing SAP in high content.

The inventors of the present invention have discovered that it ispossible, by providing a by-pass channel member for by-passing from theuppermost surface layer to the lower layers in an absorber composed bylaminating super-absorbent sheets in multiple layers, to realize anabsorber that fully cope with the flow speed of the aqueous liquid intoit and furthermore achieves a faster absorbing speed than that of theconventional thick absorber whose main component is pulp, and havecompleted the present invention.

In other words, the present invention provides the following (1) through(13).

(1) An absorber comprising a laminated absorbent member consisting oflaminated two or more super-absorbent sheets, each of which containingsuper-absorbent polymers to be capable of absorbing aqueous liquid, anda by-pass channel member which has a channel for moving the aqueousliquid fed to a first super-absorbent sheet positioned uppermost in thelaminated absorbent member from the first super-absorbent sheet toanother super-absorbent sheet, wherein the side to be fed with theaqueous liquid in the laminated absorbent member is assumed to be anupper side.

The absorber of the present invention can achieve an extremely highabsorbing speed by utilizing the absorbing capability of multiplelayers, wherein an aqueous liquid fed to the first super-absorbent sheetof the laminated super-absorbent sheets in multiple layers, i.e., thesuper-absorbent sheet positioned closest to a wearer's side when it isworn by the wearer, is distributed to other layers via the by-passchannel member.

(2) The absorber described according to (1), wherein at least one layerof the super-absorbent sheets contains 50 wt % or more of thesuper-absorbent polymer and a thickness thereof is 1.5 mm or less.

(3) The absorber according to (1) or (2), wherein all of thesuper-absorbent sheets contain 50 wt % or more of the super-absorbentpolymer and thicknesses thereof are 1.5 mm or less.

(4) The absorber according to any one of (1) to (3),

-   -   wherein at least a part of the by-pass channel member is        composed of a tube member that has a channel inside;    -   an entry end portion is formed by positioning one end of the        tube member above the first super-absorbent sheet, or by        positioning the end of the tube member such that an end portion        of the first super-absorbent sheet is inserted in the channel;        and    -   an exit end portion is formed by positioning the other end of        the tube member either above another super-absorbent sheet or        under the laminated absorbent member or both, or by positioning        the other end of the tube member such that at least one end of        another super-absorbent sheet is inserted in the channel.

(5) The absorber according to (4), wherein water-transferring sheet isprovided in the channel of the tube member.

(6) The absorber according to any one of (1) to (5),

-   -   wherein at least a part of the by-pass channel member is        composed of a concavity-and-convexity-containing sheet member        that has a concavity-and-convexity-containing surface with        concave portions and convex portions on at least one surfaces        thereof;    -   a part of the concavity-and-convexity-containing sheet member is        positioned above the first super-absorbent sheet with the        concavity-and-convexity-containing surface facing upward; and    -   another part of the concavity-and-convexity-containing sheet        member is positioned either above another respective        super-absorbent sheet or under the laminated absorbent member or        both.

(7) The absorber according to (6), wherein theconcavity-and-convexity-containing sheet member has apertures in some ofor in all of the convex portions.

(8) The absorber according to any one of (1) to (7),

-   -   wherein at least a part of the by-pass channel member is        composed of a non-woven sheet member:    -   a part of the non-woven sheet member is positioned above the        first super-absorbent sheet; and    -   another part of the non-woven sheet member is positioned either        above another super-absorbent sheet or under the laminated        absorbent member or both.

(9) The absorber according to (8), wherein the part of the non-wovensheet member is positioned above the first super-absorbent sheet so asto rise from a surface thereof.

(10) The absorber according to (8), wherein the part of the non-wovensheet member covers an area in vicinity of a center portion of the firstsuper-absorbent sheet, and functions as a skin-contact sheet.

(11) The absorber according to any one of (1) to (10),

-   -   wherein at least a part of the by-pass channel member is        composed of hydrophilic fiber or hydrophilic fiber bundle; and    -   at least the first super-absorbent sheet and another        super-absorbent sheet which makes contact therewith are sewn up        with the hydrophilic fiber or hydrophilic fiber bundle.

(12) The absorber according to (11), wherein a permeable fiber web isprovided above the first super-absorbent sheet; and at least thepermeable fiber web, the first super-absorbent sheet and said anothersuper-absorbent sheet which makes contact therewith are sewn up by aneedle-punching process.

(13) An absorbent product used to be fed with an aqueous liquid from anupper side thereof, comprising an aqueous liquid permeable sheet member,the absorber according to any one of (1) to (12), and an aqueous liquidimpermeable sheet member, from the top in this order.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an illustration of an irrigation system, explaining theprinciple of the present invention.

FIG. 2 is an illustration showing an example of the absorber of thepresent invention.

FIG. 3 is a group of conceptual diagrams explaining the movement of theaqueous liquid caused by the channels of the by-pass channel member inthe absorber of the present invention. FIGS. 3(A) through (E) aresectional views of the example shown in FIG. 2, taken along the line Xto X′.

FIGS. 4(A) through (C) are the illustrative perspective views of theexamples of the tube member, each having a channel inside.

FIG. 5 is a group of explanatory drawings showing examples of the tubemember disposition. FIGS. 5(A) through (D) are the top views and FIGS.5(A′) through (D′) are the sectional views taken along the line X to X′of each.

FIG. 6 is an illustrative perspective view of an example of theconcavity-and-convexity-containing sheet member.

FIG. 7 is an illustrative perspective view of an example of theconcavity-and-convexity-containing sheet member that has apertures inall convex portions.

FIG. 8 is a group of explanatory drawings showing examples of theconcavity-and-convexity-containing sheet member disposition. FIGS. 8(A)through (D) are the sectional views of the examples of the absorber ofthe present invention.

FIG. 9 is an illustrative sectional view showing an example of thenon-woven sheet member.

FIG. 10 is a set of explanatory drawings showing an example of thenon-woven sheet member disposition. FIG. 10(A) is a top view and FIG.10(B) is a sectional view taken along the line X to X′ of FIG. 10(A).

FIG. 11 is a sectional view of an example of the absorber of the presentinvention, explaining the disposition of the fiber bundle of thehydrophilic fiber.

FIGS. 12 (A) through (G) are the explanatory drawings, each showing anexample of planar distribution of the entries of the by-pass channelmembers.

FIG. 13 is an explanatory illustration of an evaluation test of theabsorber.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the absorber and the absorbent products of the presentinvention will be described in detail in accordance with preferredembodiments shown in accompanying drawings.

First, the principle of the present invention will be explained. Theprinciple of the present invention can be explained by making an analogyto an irrigation system that transfers irrigation water effectively andquickly to rice paddies.

FIG. 1 is an illustration of an irrigation system, explaining theprinciple of the present invention. The design concept of a conventionalabsorber obtained by laminating super-absorbent sheets in multiplelayers, when likened to an irrigation system that supplies irrigationwater to 3-terraced rice paddies the first, second and the thirdterrace, is to supply irrigation water to fill rice paddies on the firstterrace, then let the water spill over the overflow weir and flow intorice paddies on the second terrace to fill the rice paddies on thesecond terrace, and further let the water spill over the overflow weirand flow into rice paddies on the third terrace. That is, it takes timeto supply irrigation water.

In contrast to this, the design concept of the absorber of the presentinvention serves, as shown in FIG. 1, to provide irrigation channelscapable of supplying irrigation water from the rice paddies on the firstterrace to other rice paddies. This allows supplying of the irrigationwater via irrigation channels to the second and the third terrace almostsimultaneously with supplying the irrigation water to the first terrace,and thus filling of all the rice paddies with irrigation water in ashort period of time. In the absorber of the present invention, the roleof the above irrigation channels is taken by the by-pass channel memberwhich will be discussed later.

FIG. 2 is an illustration showing an example of the absorber of thepresent invention.

The absorber 1 of the present invention includes a laminated absorbentmember 10 and a by-pass channel member. Note that the by-pass channelmember is not shown in FIG. 2.

Although the laminated absorbent member 10 in FIG. 2. is composed ofthree layers of laminated super-absorbent sheets 11, 12, and 13, thereis no particular limit to the number of layers to laminate as long as 2or more layers are made.

The super-absorbent sheet used in the present invention is an absorberin extremely thin sheet form whose primary constituent is SAP. It ispreferred that the SAP content of the super-absorbent sheet is 50 wt %or more, and more preferably 60 to 95 wt %. Because the SAP content isextremely high as indicated above, the super-absorbent sheet used in thepresent invention is extremely thin. It is preferred that the thicknessof the super-absorbent sheet is 1.5 mm or less, and more preferably 1 mmor less.

There is no limit in particular to the structure or the manufacturingmethod of the super-absorbent sheet used in the present invention, aslong as it is an absorber in extremely thin sheet form with its primaryconstituent being SAP.

For example, there is a super-absorbent sheet obtained by the Air Laidmethod. The Air Laid method is a method for obtaining a super-absorbentsheet by mixing pulverized pulp and SAP, adding a binding agent to themixture, and shaping it into a sheet form. NovaThin (U.S. RegisteredTrademark), manufactured by Rayonier Inc. in the U.S., and KINOCLOTH(Registered Trademark), manufactured by Oji Kinocloth Co., Ltd., forexample, are known as super-absorbent sheets obtained by this method.

There is also a super-absorbent sheet obtained by the method of coatingan aqueous liquid permeable sheet such as non-woven fabric with a SAPdispersion slurry. The SAP dispersion slurry here is preferred to be aslurry obtained by dispersing SAP and Micro Fibrillated Cellulose (MFC)in a mixed solvent of water and ethanol. MegaThin (RegisteredTrademark), manufactured by Japan Absorbent Technology Institute, forexample, is known as a super-absorbent sheet obtained by this method.

There are also other examples such as a super-absorbent sheet obtainedby the method of applying a large amount of SAP which is supported byraised non-woven fabric, and settling it with a hot-melt binder,emulsion binder, water-soluble fiber, etc., as well as a super-absorbentsheet obtained by the method of mixing fibrous SAP and PET (polyethyleneterephthalate) fiber, and forming the mixture into a web.

The absorber of the present invention is characterized by comprising, inaddition to the afore-mentioned laminated absorbent member, a by-passchannel member which has a channel for moving the aqueous liquid (urine,for example) fed to the first super-absorbent sheet 11 which ispositioned at the uppermost part of the laminated absorbent member, fromthe first super-absorbent sheet 11 to another super-absorbent sheet(super-absorbent sheets 12 and 13 in FIG. 2). Note that in the presentspecification, the side where the aqueous liquid is fed is referred toas the “upper” side and the opposite side is referred to as the “bottom”side of the laminated absorbent member More specifically, the sidecloser to a user's skin is referred to as the “upper” side and the sideaway from the skin is referred to as the “bottom” side when the useractually wears the absorbent product of the present invention using theabsorber of the present invention.

There is no limit in particular to the shape, size, material,disposition, etc. of the by-pass channel member used in the presentinvention, as long as it has a channel to move the aqueous liquid fromthe first super-absorbent sheet 11 to the other super-absorbent sheets12 and 13.

First, the function of the by-pass channel member will be explained.

FIG. 3 is a group of conceptual diagrams explaining the movement of theaqueous liquid caused by the channel of the by-pass channel member inthe absorber of the present invention. FIGS. 3(A) through (E) aresectional views of the example shown in FIG. 2, taken along the line Xto X′. Note that the present invention shall not be limited by these.

In the example shown in FIG. 3(A), a by-pass channel member is providedto move the aqueous liquid 5 fed to the first super-absorbent sheet 11,from the first super-absorbent sheet 11 to the top of anothersuper-absorbent sheet 13.

In the example shown in FIG. 3(B), a by-pass channel member is providedto move the aqueous liquid 5 fed to the first super-absorbent sheet 11,from the first super-absorbent sheet 11 downward beneath anothersuper-absorbent sheet 13 (that is, between the super-absorbent sheet 13and the back-sheet 2) in the center area in the X-X′ direction, to thetop of the super-absorbent sheet 13 on both sides adjacent to thiscenter area, and to the top of the super-absorbent sheet 12 on bothfurther sides of the above.

In the example shown in FIG. 3(C), a by-pass channel member is providedto move the aqueous liquid 5 fed to the first super-absorbent sheet 11,from the first super-absorbent sheet 11 downward beneath thesuper-absorbent sheet 13. Furthermore, a by-pass channel member isprovided to circumvent the ends of the super-absorbent sheets 11, 12 and13.

In the example shown in FIG. 3(D), a by-pass channel member is providedto move the aqueous liquid 5 fed to the first super-absorbent sheet 11,from the first super-absorbent sheet 11 downward beneath thesuper-absorbent sheet 13 at the left end of the absorber 1 as shown inFIG. 3(D), and from the first super-absorbent sheet 11 to the top of thesuper-absorbent sheet 13 at the right end of the absorber 1.Furthermore, a by-pass channel member is provided to circumvent the endsof the super-absorbent sheets 11, 12 and 13.

In the example shown in FIG. 3(E), a by-pass channel member is providedto move the aqueous liquid 5 fed to the first super-absorbent sheet 11,from the first super-absorbent sheet 11 to the top of thesuper-absorbent sheet 12 and to the top of the super-absorbent sheet 13,respectively. Furthermore, a by-pass channel member is provided tocircumvent the ends of the super-absorbent sheets 11 and 12.

The disposition of the by-pass channel member can be determinedaccording to such conditions as the shape, material, and characteristicsthereof.

As described above, movement and introduction of the aqueous liquidbetween the layers is carried out effectively by the by-pass channelmember. In other words, a large amount of the aqueous liquid such asurine fed in a short period of time to the surface of the firstsuper-absorbent sheet 11, can be moved rapidly to the othersuper-absorbent sheet(s) 12 and/or 13.

As long as it has a channel to move the aqueous liquid from the firstsuper-absorbent sheet 11 to other super-absorbent sheets 12 and 13,there is no particular limit to the by-pass channel member used in thepresent invention, as mentioned above, but the followings may bepreferably used: (1) a tube member that has a channel inside, (2) aconcavity-and-convexity-containing sheet member that has at least oneconcavity-and-convexity-containing surface having concave portions andconvex portions (hereinafter referred to simply as“concavity-and-convexity-containing sheet member”), (3) a non-wovensheet member, and (4) hydrophilic fiber or its fiber bundle. One ofthese is used alone or two or more of these are used in combination.

Hereinafter, the above (1) through (4) listed as preferred by-passchannel members will be explained.

(1) Tube member that has a channel inside.

There is no particular limit to the shape, size, material, manufacturingmethod, etc. of the tube member with a channel inside of it. FIGS. 4(A)through (C) are the illustrative perspective views of the examples ofthe tube member, each having a channel inside. These tube members may beobtained by, for example, forming a flat tube using film.

In the tube member 21 shown in FIG. 4(A), the entry end portion 21 a andthe exit end portion 21 b are of the same shape, and the length stayssame along the line of channel.

In the tube member 22 shown in FIG. 4(B), the entry end 22 a is of thesame shape as that of FIG. 4(A), but the exit end portion 22 b has atriangular notch on one side. Therefore, when the exit end portion 22 bis positioned such that the side with the triangular notch faces upward,the aqueous liquid is quickly distributed to the super-absorbent sheetlocated above the exit end portion 22 b, and when the exit end portion22 b is positioned such that the side with the triangular notch facesdownward, the aqueous liquid is quickly distributed to thesuper-absorbent sheet positioned under the exit end portion 22 b.

In the tube member 23 shown in FIG. 4(C), the entry end portion 23 a isof the same shape as that of FIG. 4(A), but the exit end portion 23 bhas an almost semicircle notch on both sides. Therefore, in the portionwhere the tube length along the line of the channel is shortest due tothese notches of the exit end portion 23 b, the aqueous liquid isdistributed quickly to the super-absorbent sheets.

There is no limit in particular to the size of the tube member. Althoughan example of the size of the tube member is shown in FIGS. 4(A) through(C), the present invention shall not be limited by this.

As the material for the tube member, followings can be exemplified: anaqueous liquid impermeable film made of resin such as PE (polyethylene),PP (polypropylene), PVA (polyvinyl alcohol), and urethane; and awater-resistant non-woven fabric such as SMS non-woven fabric (ofthree-layer structure of spunbond/meltblown/spunbond), and SMMSnon-woven fabric (non-woven fabric of four-layer structure ofspunbond/meltblown/meltblown/spunbond).

As the tube member, a tube in a form similar to what is obtained bycutting the bottom of a PE bag of 50 to 100 mm in width, 100 to 200 mmin length and 5 to 20 μm in thickness for household use; or a tubeobtained by cutting a tube similar to a rain-drop protection PE tube forwet umbrellas to the appropriate length, for example, can be used.

Next, the disposition of the tube member is explained.

FIG. 5 is a group of explanatory drawings showing examples of the tubemember disposition. In FIG. 5, the absorber 1 of the present inventionhas a laminated absorbent member 10 composed of three layers ofsuper-absorbent sheets 11, 12, and 13, a tube member 20, and aback-sheet 2 provided under a super-absorbent sheet 13. FIGS. 5(A)through (D) are the top views and FIGS. 5(A′) through (D′) are thesectional views taken along the line X to X′ of each.

One end of the tube member is positioned above the first super-absorbentsheet or is placed in such a way that the end portion of the firstsuper-absorbent sheet is inserted into the channel of the tube member,to thereby form an entry end portion.

In each example shown in FIGS. 5(A′) through (D′), one end of the tubemember 20 is positioned in such a way that the end portion of the firstsuper-absorbent sheet 11 is inserted into the channel of the tubemember, to form the entry end portion 20 a. The present invention,however, shall not be limited by this, and one end of the tube membermay also be placed above the first super-absorbent sheet to form theentry end portion.

Furthermore, the other end of the tube member is positioned either aboveanother super-absorbent sheet or under the laminated absorbent member orboth, or is positioned in such a way that at least one of the endportions of another super-absorbent sheet is inserted into the channelof the tube member, to form an exit end portion.

In each example shown in FIGS. 5(A′), (C′), and (D′), the other end ofthe tube member 20 is positioned above the super-absorbent sheet 13(that is, between the super-absorbent sheet 12 and the super-absorbentsheet 13), to form the exit end portion 20 b. Further, in the exampleshown in FIG. 5(B′), the other end of the tube member 20 is positionedunder the laminated absorbent member 10 (that is, between thesuper-absorbent sheet 13 which is the lowermost layer of the laminatedabsorbent member 10 and the back-sheet 2), to form the exit end portion20 b. The present invention, however, shall not be limited by this, andthe exit end portion may also be formed such that at least one of theends of another super-absorbent sheet is inserted into the channel ofthe tube member.

In each example shown in FIGS. 5(A) through (D), an exposed portion ofthe first super-absorbent sheet 11 (a portion that is not inserted intothe channel of the tube member 20) is small in comparison with the sizeof the surface of the super-absorbent sheet 12. Accordingly, while themajor part of the fed aqueous liquid flows into the channel via thisfirst super-absorbent sheet 11 being partially absorbed thereinto, theaqueous liquid which overflows from the first super-absorbent sheet 11sideward moves directly to not through the channel, and then is absorbedby the second super-absorbent sheet 12.

In the example shown in FIG. 5(A), the first super-absorbent sheet 11covers the super-absorbent sheet 12 fully in the length along the lineof X-X′.

In the example shown in FIG. 5(B), while the end portion of the firstsuper-absorbent sheet 11 is deeply inserted into the tube exceeding thebent section of the tube member 20, the super-absorbent sheet 12 isexposed when viewed from above the absorber 1.

In the example shown in FIG. 5(C), two tube members 20 are provided andthe end portions of the first super-absorbent sheet 11 are deeplyinserted into the tubes exceeding the bent sections of respective tubemembers 20, but because the super-absorbent sheet 11 is longer than thesuper-absorbent sheet 12, it covers the super-absorbent sheet 12 fullyin the length along the line of X-X′.

The example shown in FIG. 5(D) represents the reversedvertical-to-horizontal positional relationship of the example shown inFIG. 5(C).

It is preferred that the tube members 20 are positioned so as to goaround the end portions of the super-absorbent sheets as shown in eachexample in FIG. 5.

In each example shown in FIG. 5, as described above, the end portion ofthe super-absorbent sheet 11 is inserted into the channel of the tubemember 20. This leads to a preferable result in which the distributionefficiency of the aqueous liquid is improved because the liquid isintroduced to the channel. This leads to another preferable result inwhich disruption of the flow of the aqueous liquid due to deformation ofthe tube member 20 during use is prevented.

Note that in case the end portion of the super-absorbent sheet 11 isinserted into the channel of the tube member 20, the end portion may beinserted straightforward or inserted while being bent.

In the absorber of the present invention, it is also acceptable toseparately provide a water-transferring sheet to conduct the aqueousliquid to the channel. The water-transferring sheet is a sheet that hasthe characteristics of enabling the transferring of the aqueous liquid(water-transferability) by using capillary action, and woven fabric ornon-woven fabric can be used for it.

(2) Concavity-and-Convexity-Containing Sheet Member

In the concavity-and-convexity-containing sheet member that has at leastone concavity-and-convexity-containing surface with concave portions andconvex portions, a number of concave portions in a series function asthe channel for the aqueous liquid. There is no limit in particular tothe concavity-and-convexity-containing sheet member's shape, size,material, manufacturing method, etc., as long as it has at least oneconcavity-and-convexity-containing surface with concave portions andconvex portions.

FIG. 6 is an illustrative perspective view of an example of theconcavity-and-convexity-containing sheet member. Theconcavity-and-convexity-containing sheet member 31 shown in FIG. 6 has anumber of projections 32 that form the convex portions.

As to the size of the concavity and convexity of theconcavity-and-convexity-containing sheet member, its handling, cost,etc. being taken into account, it is preferred that the projectionsforming the convex portions are 0.3 mm or greater in height, morepreferably 0.5 to 1.5 mm.

It is acceptable either that the concave portions and convex portionsare provided on one surface only or that they are provided on bothsurfaces.

As the material for the concavity-and-convexity-containing sheet member,an aqueous liquid impermeable film made of resin such as PE, PP, PVA,and urethane, and a water-resistant non-woven fabric, such as SMSnon-woven and SMMS non-woven can be listed as examples.

In the concavity-and-convexity-containing sheet member, apertures canalso be provided in some of or all of the convex portions.

FIG. 7 is an illustrative perspective view of an example of aconcavity-and-convexity-containing sheet member that has apertures inall convex portions. The concavity-and-convexity-containing sheet member33 that has apertures in convex portions as shown in FIG. 7 has a numberof projections 34 that form the convex portions, each projection 34having an aperture 35 at the top of it.

With the concavity-and-convexity-containing sheet member that does nothave apertures in convex portions as shown in FIG. 6, only the concaveportions function as the channel for the aqueous liquid if it is made ofa material impermeable to aqueous liquid; but with theconcavity-and-convexity-containing sheet member that has apertures inconvex portions as shown in FIG. 7, these apertures also function as thechannels for the aqueous liquid even if it is made of an aqueous liquidimpermeable material. In other words, the aqueous liquid moves via theapertures from one side of the concavity-and-convexity-containing sheetmember to the other side. The use of suchconcavity-and-convexity-containing sheet member, therefore, ispreferably made when it covers a relatively large area of the surface ofthe first super-absorbent sheet.

The apertures may be provided only in some of the convex portions or inall of the convex portions. Furthermore, though there is no limit inparticular to the number of apertures per unit area, 1.0 to 100apertures/cm² is preferable.

The concavity-and-convexity-containing sheet member has an advantagethat the flow of the aqueous liquid is not disrupted even when someconvex portions are deformed during use.

Next, disposition of the concavity-and-convexity-containing sheet memberwill be explained.

FIG. 8 is a group of explanatory drawings showing examples of theconcavity-and-convexity-containing sheet member disposition. In FIG. 8,the absorber 1 of the present invention has a laminated absorbent member10 composed of two layers of super-absorbent sheets 11 and 12, aconcavity-and-convexity-containing sheet member 30, and a back-sheet 2provided under the super-absorbent sheet 12. FIGS. 8(A) through (D) arethe sectional views of examples of the absorber of the presentinvention.

In each example shown in FIGS. 8(A) through (D), a portion 30 a of theconcavity-and-convexity-containing sheet member 30 is positioned to behigher than the super-absorbent sheet 11 in such a way that theconcavity-and-convexity-containing surface (not shown) faces upward.

In the example shown in FIG. 8(A), a portion 30 a of theconcavity-and-convexity-containing sheet member 30 is positioned to behigher than the super-absorbent sheet 11 in such a way that it partiallycovers the super-absorbent sheet 11. Also, other portions 30 b of theconcavity-and-convexity-containing sheet member 30 are positioned abovethe super-absorbent sheet 12 (that is, between the first super-absorbentsheet 11 and the super-absorbent sheet 12). Therefore, the aqueousliquid fed to the first super-absorbent sheet 11 is absorbed in thefirst super-absorbent sheet 11 in part, but the rest moves via theconcavity-and-convexity-containing sheet member 30 to thesuper-absorbent sheet 12 where it is diffused and absorbed entirely onits surface.

In the example shown in FIG. 8(B), a portion 30 a of theconcavity-and-convexity-containing sheet member 30 is positioned to behigher than the super-absorbent sheet 11, in such a way that itpartially covers the super-absorbent sheet 11. Also, the other portions30 b of the concavity-and-convexity-containing sheet member 30 arepositioned under the laminated absorbent member 10 (that is, between thesuper-absorbent sheet 12 which makes the lowermost layer of thelaminated absorbent member and the back-sheet 2).

In the example shown in FIG. 8(C), portions 30 a of theconcavity-and-convexity-containing sheet member 30 are positioned to behigher than the super-absorbent sheet 11 in such a way that they do notcover a part of the super-absorbent sheet 11. Also, other portions 30 bof the concavity-and-convexity-containing sheet member 30 are positionedunder the laminated absorbent member 10.

In the example shown in FIG. 8(D), portions 30 a of theconcavity-and-convexity-containing sheet member 30 are positioned to behigher than the super-absorbent sheet 11, in such a way that they do notcover a part of the super-absorbent sheet 11 but rather that theyproject and stand up. Here, elastics 36, such as polyurethane filamentsare inserted inside the portions 30 a of theconcavity-and-convexity-containing sheet member 30. Also, the otherportions 30 b of the concavity-and-convexity-containing sheet member 30are positioned under the laminated absorbent member 10.

In the examples shown in FIGS. 8(B) through (D), therefore, the aqueousliquid fed to the first super-absorbent sheet 11 is absorbed in thefirst super-absorbent sheet 11 in part, but the rest moves via theconcavity-and-convexity-containing sheet member 30 to the bottom surfaceof the super-absorbent sheet 12 where it is diffused and absorbedentirely on its surface.

(3) Non-Woven Sheet Member

In a non-woven sheet member, air gaps inside thereof function as thechannel for the aqueous liquid. There is no limit in particular to thenon-woven sheet member's shape, size, material, manufacturing method,etc., but one that is bulky and is of high resilience is preferred.

“High resilience” here means, in general, having the characteristics ofgreat compression-resistance, i.e., not getting flattened when a load isapplied. It is preferred in particular that it has high resilience anddoes not get flattened when it is wet (in use).

The preferred material of high resilience used for the non-woven sheetmember is a hydrophobic synthetic fiber with a high Young's modulus in awet environment preferably of 3 d or above or more preferably of coarsedenier of 5 to 12 d, or even more preferably a synthetic fiber withcrimps. A more specific example is a composite fiber of bi-componentpolyester, often used for stuffing of bottom futon mats. As bulkiness isexpressed as a measure of basis weight and apparent specific gravity, inthe present invention, the preferred basis weight is 20 mg/m² or moreand apparent specific gravity 0.1 g/cm³ or less. A bulky non-wovenfabric generally used as a temporary retention layer or a so-called“acquisition layer” in absorbent products can also be used.

There is no restriction in particular on the method of manufacturingnon-woven fabric by using these fibers; the thermal-bond non-woven (forexample, the non-woven fabric composed of a bulky water-impermeablephase of low apparent density, constructed in the form of laminate ofthe hydrophobic and hydrophilic fiber layers and a water-permeable phaseof high apparent density, constructed in the form of the compressedmixture of hydrophobic and hydrophilic fibers, which is suggested by theinventors of the present invention in JP 2002-20957 A) and the non-wovenfabric in a multi-layered structure (for example, the composite sheetmade by bonding a paper layer or non-woven fabric layer with a flat andsmooth surface and the fiber web layer with a bulky and uneven surfacealternately with one another, which is suggested by the inventors of thepresent invention in the specification of Japan Patent Application No.2001-297161 and the specification of Japan Patent Application No.2001-297162), for example, are preferred.

FIG. 9 is an illustrative sectional view showing an example of thenon-woven sheet member. The non-woven sheet member 41 shown in FIG. 9 isa bulky non-woven fabric composite of a PP spunbond non-woven fabric 42and a polyester fiber web 43. A more specific example will be a bulkynon-woven fabric of about 1.5 mm thickness, obtainable by compositingwith spot-thermal-bonding a PP spunbond non-woven fabric of 13 g/m² withan average denier of 2.2 d (manufactured by Avgol) and a carded-web (30g/m²) of the 8 d×61 mm polyester fiber (manufactured by Unitika Ltd.),which is a PE/PET side-by-side composite fiber.

Next, the disposition of the non-woven sheet member will be explained.

The disposition of the non-woven sheet member is the same as that of theabove-described disposition of the concavity-and-convexity-containingsheet member, but it will be explained here with the more specificexamples.

FIG. 10 is a set of explanatory drawings showing an example of thenon-woven sheet member disposition. In FIG. 10, the absorber 1 of thepresent invention has the laminated absorbent member 10 composed of twolayers of super-absorbent sheets 11 and 12, the non-woven sheet member40, and the back-sheet 2 provided under the super-absorbent sheet 12.FIG. 10(A) is a top view and FIG. 10(B) is a sectional view taken alongthe line X-X′ of FIG. 10(A).

In the example shown in FIG. 10, a portion 40 a of the non-woven sheetmember 40 is positioned above the super-absorbent sheet 11, in such away that it partially covers the super-absorbent sheet 11. Also, otherportions 40 b of the non-woven sheet member 40 are positioned above thesuper-absorbent sheet 12 (that is, between the first super-absorbentsheet 11 and the super-absorbent sheet 12). Furthermore, thesuper-absorbent sheet 12 forms a side-guard 12 a at each end of theabsorber in the direction of X-X′, by being folded in such a manner topartially cover both ends of the first super-absorbent sheet 11.Therefore, the aqueous liquid fed to the first super-absorbent sheet 11is diffused into both the first super-absorbent sheet 11 and thesuper-absorbent sheet 12 and thus quickly absorbed.

In the absorber of the present invention, covering the area in vicinityof the center portion of the first super-absorbent sheet 11 with aportion 40 a of the non-woven sheet member 40 to function as askin-contact sheet is one of the preferred embodiments.

(4) Hydrophilic Fiber or Its Fiber Bundle

In the hydrophilic fiber or its fiber bundle, a channel is formed as theaqueous liquid flows through it by capillary action.

FIG. 11 is a sectional view of an example of the absorber of the presentinvention, explaining the disposition of the fiber bundle of thehydrophilic fiber. In FIG. 11, the absorber 1 of the present inventionhas a laminated absorbent member 10 composed of two layers ofsuper-absorbent sheets 11 and 12, a fiber bundle of the hydrophilicfiber 50, and a back-sheet 2 provided under the super-absorbent sheet12.

In the example shown in FIG. 11, an acquisition web 51, which is awater-permeable fiber web, is provided over the first super-absorbentsheet 11, and the acquisition web 51, the first super-absorbent sheet 11and the super-absorbent sheet 12 are sewn up together with the fiberbundle of the hydrophilic fiber 50. A carded web composed of ahydrophilic-treated polyester fiber, for example, may be used as theacquisition web 51.

Note that provision of the acquisition web 51 is not a requirement inthe present invention. It will be acceptable as long as the firstsuper-absorbent sheet 11 and its tangent super-absorbent sheet 12 aresewn up together.

The first super-absorbent sheet 11 and the super-absorbent sheet 12 canbe sewn up by a needle-punching process, for example.

The explanation so far has been of the preferred by-pass channelmembers, but the by-pass channel members used in the present inventionare not limited to these. It is acceptable as long as it has the channelto move the aqueous liquid, fed to the first super-absorbent sheetpositioned at the uppermost part of the laminated absorbent member, fromthe first super-absorbent sheet to another super-absorbent sheet. Inother words, it is acceptable if the by-pass channel member has entriesand exits along with channels to link therebetween.

The entries of the by-pass channel may be one aperture or more than one;either is acceptable. The entries of the by-pass channel are mostcommonly provided on the first super-absorbent sheet, but when there isan acquisition layer or a skin-contacting layer on the firstsuper-absorbent sheet, it is also acceptable to position the entries onthem. Furthermore, in case a super-absorbent sheet other than the firstsuper-absorbent sheet is exposed when viewed from the top, it is alsoacceptable to position the entries on the exposed super-absorbent sheet.

FIGS. 12(A) through (G) are the explanatory drawings, each showing anexample of planar distribution of the entries of the by-pass channelmembers.

In FIG. 12(A), the entries 15 a of the by-pass channel member 15 arepositioned lengthwise on both ends of the first super-absorbent sheet 11located at the uppermost part of the laminated absorbent member 10.

In FIG. 12(B), the entry 15 a of the by-pass channel member 15 ispositioned in the marginal region all around the first super-absorbentsheet 11.

In FIG. 12(C), the entry 15 a of the by-pass channel member 15 ispositioned, in the form of a relatively wide band, in the centerwidthwise of the first super-absorbent sheet 11, and extending in alongitudinal direction.

In FIG. 12(D), the entries 15 a of the by-pass channel member 15 arepositioned, in the form of relatively narrow plural bands (three bandsin this example), in the center and at both ends widthwise of the firstsuper-absorbent sheet 11.

In FIG. 12(E), the entries 15 a of the by-pass channel member 15 arepositioned, in the form of relatively narrow plural bands (three in thisexample), in the center widthwise of the first super-absorbent sheet 11.

In FIG. 12(F), the entries 15 a of the by-pass channel member 15 arepositioned, in the form of a cross, in the center widthwise and thecenter lengthwise of the first super-absorbent sheet 11.

In FIG. 12(G), the entries 15 a of the by-pass channel member 15 arepositioned, in the form of numerous dots, all over the surface of firstsuper-absorbent sheet 11.

The forms and shapes as well as the planar distribution of entries ofthe by-pass channel members are not limited to the above; they can bedetermined according to such factors as the design of the absorber ofthe present invention and the material used for the by-pass channelmembers.

The disposition, shapes, forms, etc. of the exits of the by-pass channelmembers can be determined according to the super-absorbent sheet formoving the aqueous liquid and the disposition of the exits on thesuper-absorbent sheet.

The absorber of the present invention only has to include at least oneby-pass channel member that has the channel to move the aqueous liquidfed to the first super-absorbent sheet from the first super-absorbentsheet to another super-absorbent sheet, and in addition to this, it mayalso include the by-pass channel member to move the aqueous liquidbetween other super-absorbent sheets (between the super-absorbent sheet12 and the super-absorbent sheet 13 in FIG. 2, for example).

The absorber of the present invention can also include a member thatallows diffusion, within the same super-absorbent sheet, of the fed-inaqueous liquid.

In the present invention, the by-pass channel member does not have to bean independent member, but instead its function may be fulfilled by asuper-absorbent sheet, or a skin-contact sheet, back-sheet, gathers,etc., that are commonly used in absorbent products, taking a differentform.

The role of the by-pass channel members described above is todramatically improve the absorbing speed of the entire absorber, as wellas to enable efficient utilization of the entire surface of every layerof the super-absorbent sheets.

In a conventional absorber that uses super-absorbent sheets, ifexcretion of urine takes place in a recumbent position, for example,urine would be concentrated on one side of the absorber due togravitation. Similarly, in a procumbent position, urine would beconcentrated in the lower side of the absorber (the side away from thewearer's skin); in the supine position, urine would be concentrated inthe upper side of the absorber (the side nearer to the wearer's skin);and in the standing position or sitting position, urine would beconcentrated in the central region of the absorber. In a conventionalabsorber, therefore, absorption of urine is carried out locally only atthe section where urine is concentrated, so, if it does not have enoughabsorbing capacity, urine would overflow and eventually leak. At thesame time, a large area in the absorber will remain hardly absorbing.

Because the wearer's position when urinating varies regardless of theabsorber's structure, for the conventional absorber to be able to fullyabsorb urine in any possible position, it has been necessary to giveenough reserve of absorbing capability to all parts of the absorber, so,inevitably, twice or sometimes four times as much absorbing capabilityhad to be given to the absorber.

In contrast to this, in the absorber of the present invention, becauseurine that has been fed into one part of the absorber is absorbed afterit moves rapidly via the channels of the by-pass channel members to theoverall surface of each super-absorbent sheet, and because no blockingis caused, the absorbing capacity of the absorber is fulfilled withoutany loss, and there is very little possibility of leakage. According tothe present invention, therefore, because the mass and surface area ofthe super-absorbent sheets required for the absorber can be dramaticallyreduced, an extremely compact absorber with excellent absorbing capacitycan be realized.

The absorbent product of the present invention is used to be fed withthe aqueous liquid to it from the top; the absorbent product includesthe aqueous liquid permeable sheet member, the absorber of the presentinvention as described above, and the aqueous liquid impermeable sheetmember, from the top to the bottom in this order.

For the aqueous liquid permeable sheet member, what is commonly used asa skin-contact sheet can be used. More specifically, PP non-woven,polyolefin-polyester non-woven as well as their cotton blend, forexample, can be used.

For the aqueous liquid impermeable sheet member, what is commonly usedas the back-sheet can be used. More specifically, a PE film as well as alaminated PE film with PP non-woven thereunder, for example, can beused.

The absorbent product of the present invention only has to have theabove structure, and it can also have other members aside from theabove, such as inside-gather and outside-gather.

Since using the absorber of the present invention, the absorbent productof the present invention is extremely compact, has excellent absorbingcapability and is free from the risk of leakage.

EXAMPLE

Hereinafter, the present invention will be explained in detail byshowing an example, but the present invention shall not be limited bythis.

The absorber shown in FIG. 10 was made.

For the super-absorbent sheets 11 and 12, the sheets made by coating SAPdispersion slurry on polyester non-woven fabric (MegaThin (RegisteredTrademark in Japan) manufactured by Japan Absorbent TechnologyInstitute, SAP: 180 g/m²) was used.

For the non-woven sheet member 40, a bulky composite non-woven sheetmade of PP spunbond non-woven fabric 42 and polyester fiber web 43 shownin FIG. 9 was used. More specifically, a bulky non-woven sheet of about1.5 mm thickness was used, which was obtained by compositing withspot-thermal-bonding PP spunbond non-woven fabric of 13 g/m² withaverage denier of 2.2 d (manufactured by Avgol) and the carded-web (30g/m²) of the 8 d×61 mm polyester fiber (manufactured by Unitika Ltd.),which is a PE/PET side-by-side composite fiber.

For the back-sheet 2, the concavity-and-convexity-containing PE film (20g/m²) manufactured by Tredeger was used.

Other dimensions of each member are shown in FIG. 10(A).

Next, using this absorber 1, absorbency and diffusion were evaluated.

FIG. 13 is an explanatory illustration of an evaluation test of theabsorber. In FIG. 13, only the super-absorbent sheet 11 of the absorber1 is shown, and the rest of the members are omitted.

As shown in FIG. 13, a weight 61 of 0.1 psi (70.3 g/cm²), which has aninlet 62 of 2 cm inside diameter, is placed in the center of the firstsuper-absorbent sheet 11, and 100 mL of saline were added three times,thus, 300 mL in total, from the inlet 62. Intervals between the end ofthe first addition and the beginning of the second addition and betweenthe end of the second addition and the beginning of the third additionwere both 10 minutes.

The absorbing speed and diffusion area were measured at each addition.The absorbing speed was evaluated by measuring the time period from thebeginning of each addition to when it was visually confirmed that 100 mLof saline was completely absorbed. The diffusion area was obtained byfirst taking a photo of the absorber when complete absorption of added100 mL saline had been visually confirmed, and then measuring on thephoto the wetted area resulting from absorbing the saline.

The results are shown in Table 1. An absorber of the exact samestructure as that of the absorber 1 of the present invention except forthe missing non-woven sheet member 40 was used as a Comparative Example.TABLE 1 Absorbing Speed Diffusion Area (sec/100 mL) (cm²) 1^(st) 2^(nd)3^(rd) 1^(st) 2^(nd) 3^(rd) Example 14 17 15 200 270 300 ComparativeExample 168 228 345 90 132 145

Table 1 indicates a 10 times faster absorbing speed and twofoldimprovement in the diffusion area of the absorber of the presentinvention having a by-pass channel member, compared to the absorber ofthe Comparative Example having no by-pass channel member.

INDUSTRIAL APPLICABILITY

As explained above, the absorber of the present invention realizes aremarkable improvement in the absorbing speed of aqueous liquid andexpansion of diffusion area, while maintaining various features requiredfor absorbers, such as flexibility. This was realized by providing inthe absorber comprising laminated two or more super-absorbent sheets,the by-pass channel member that has the channel for moving the aqueousliquid fed to the first super-absorbent sheet which is situated at theuppermost part of the laminated absorbent member, from this firstsuper-absorbent sheet to another super-absorbent sheet positioned below.When applied in various absorbent products, the absorber of the presentinvention is able to exhibit significant positive effects, includingensuring prevention of accidents such as leakage.

1. An absorber comprising a laminated absorbent member consisting oflaminated two or more super-absorbent sheets, each of which containingsuper-absorbent polymers to be capable of absorbing aqueous liquid, anda by-pass channel member which has a channel for moving the aqueousliquid fed to a first super-absorbent sheet positioned uppermost in thelaminated absorbent member from the first super-absorbent sheet toanother super-absorbent sheet, wherein the side to be fed with theaqueous liquid in the laminated absorbent member is assumed to be anupper side.
 2. The absorber according to claim 1, wherein at least onelayer of the super-absorbent sheets contains 50 wt % or more of thesuper-absorbent polymer and a thickness thereof is 1.5 mm or less. 3.The absorber according to claim 2, wherein all of the super-absorbentsheets contain 50 wt % or more of the super-absorbent polymer andthicknesses thereof are 1.5 mm or less.
 4. The absorber according toclaim 1, wherein at least a part of the by-pass channel member iscomposed of a tube member that has a channel inside; an entry endportion is formed by positioning one end of the tube member above thefirst super-absorbent sheet, or by positioning the end of the tubemember such that an end portion of the first super-absorbent sheet isinserted in the channel; and an exit end portion is formed bypositioning the other end of the tube member either above anothersuper-absorbent sheet or under the laminated absorbent member or both,or by positioning the other end of the tube member such that at leastone end of another super-absorbent sheet is inserted in the channel. 5.The absorber according to claim 4, wherein water-transferring sheet isprovided in the channel of the tube member.
 6. The absorber according toclaim 1, wherein at least a part of the by-pass channel member iscomposed of a concavity-and-convexity-containing sheet member that has aconcavity-and-convexity-containing surface with concave portions andconvex portions on at least one surfaces thereof; a part of theconcavity-and-convexity-containing sheet member is positioned above thefirst super-absorbent sheet with the concavity-and-convexity-containingsurface facing upward; and another part of theconcavity-and-convexity-containing sheet member is positioned eitherabove another super-absorbent sheet or under the laminated absorbentmember or both.
 7. The absorber according to claim 6, wherein theconcavity-and-convexity-containing sheet member has apertures in some ofor in all of the convex portions.
 8. The absorber according to claim 1,wherein at least a part of the by-pass channel member is composed of anon-woven sheet member; a part of the non-woven sheet member ispositioned above the first super-absorbent sheet; and another part ofthe non-woven sheet member is positioned either above anothersuper-absorbent sheet or under the laminated absorbent member or both.9. The absorber according to claim 8, wherein the part of the non-wovensheet member is positioned above the first super-absorbent sheet so asto rise from a surface thereof.
 10. The absorber according to claim 8,wherein the part of the non-woven sheet member covers an area invicinity of a center portion of the first super-absorbent sheet, andfunctions as a skin-contact sheet.
 11. The absorber according to claim1, wherein at least a part of the by-pass channel member is composed ofhydrophilic fiber or hydrophilic fiber bundle; and at least the firstsuper-absorbent sheet and another super-absorbent sheet which makescontact therewith are sewn up with the hydrophilic fiber or hydrophilicfiber bundle.
 12. The absorber according to claim 11, wherein apermeable fiber web is provided above the first super-absorbent sheet;and at least the permeable fiber web, the first super-absorbent sheetand said another super-absorbent sheet which makes contact therewith aresewn up by a needle-punching process.
 13. An absorbent product used tobe fed with an aqueous liquid from an upper side thereof, comprising anaqueous liquid permeable sheet member, the absorber according to claim1, and an aqueous liquid impermeable sheet member, from the top in thisorder.